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Ding X, Wang Y, Gui Y, Yang C. Two-Stage Mixed-Dye-Based Isothermal Amplification with Ribonuclease-Cleavable Enhanced Probes for Dual-Visualization Detection of SARS-CoV-2 Variants of Interest. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2401988. [PMID: 38829265 PMCID: PMC11304323 DOI: 10.1002/advs.202401988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 05/17/2024] [Indexed: 06/05/2024]
Abstract
Rapid and visual detection of SARS-CoV-2 variants is vital for timely assessment of variant transmission in resource-limited settings. Here, a closed-tube, two-stage, mixed-dye-based isothermal amplification method with ribonuclease-cleavable enhanced probes (REP), termed REP-TMAP, for dual-visualization detection of SARS-CoV-2 variants including JN.1, BA.2, BA.4/5, and Delta is introduced. The first stage of REP-TMAP is reverse transcription recombinase polymerase amplification and the second stage is dual-visualization detection synergistically mediated by the REP and the mixed dyes of cresol red and hydroxy naphthol blue. In REP-TMAP reaction, the color change under ambient light indicates SARS-CoV-2 infection, while the fluorescence change under blue light excitation specifies variant type. On detecting transcribed RNA of SARS-CoV-2 spike gene, this assay is rapid (within 40 min), highly sensitive (10-200 copies per reaction), and highly specific (identification of single-base mutations). Furthermore, the assay has been clinically validated to accurately detect JN.1, BA.2, and BA.4/5 variants from 102 human oropharyngeal swabs. The proposed assay therefore holds great potentials to provide a rapid, dual-visualization, sensitive, specific, point-of-care detection of SARS-CoV-2 variants and beyond.
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Affiliation(s)
- Xiong Ding
- Key Laboratory of Environmental Medicine and EngineeringMinistry of EducationDepartment of Nutrition and Food HygieneSchool of Public Health, Southeast UniversityNanjing210009P. R. China
| | - Yaru Wang
- Key Laboratory of Environmental Medicine and EngineeringMinistry of EducationDepartment of Nutrition and Food HygieneSchool of Public Health, Southeast UniversityNanjing210009P. R. China
| | - Yuxin Gui
- Key Laboratory of Environmental Medicine and EngineeringMinistry of EducationDepartment of Nutrition and Food HygieneSchool of Public Health, Southeast UniversityNanjing210009P. R. China
| | - Chuankun Yang
- Center of Clinical Laboratory MedicineZhongda Hospital, Southeast UniversityNanjing210009P. R. China
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2
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Łazowski K, Woodgate R, Fijalkowska IJ. Escherichia coli DNA replication: the old model organism still holds many surprises. FEMS Microbiol Rev 2024; 48:fuae018. [PMID: 38982189 PMCID: PMC11253446 DOI: 10.1093/femsre/fuae018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Revised: 06/26/2024] [Accepted: 07/08/2024] [Indexed: 07/11/2024] Open
Abstract
Research on Escherichia coli DNA replication paved the groundwork for many breakthrough discoveries with important implications for our understanding of human molecular biology, due to the high level of conservation of key molecular processes involved. To this day, it attracts a lot of attention, partially by virtue of being an important model organism, but also because the understanding of factors influencing replication fidelity might be important for studies on the emergence of antibiotic resistance. Importantly, the wide access to high-resolution single-molecule and live-cell imaging, whole genome sequencing, and cryo-electron microscopy techniques, which were greatly popularized in the last decade, allows us to revisit certain assumptions about the replisomes and offers very detailed insight into how they work. For many parts of the replisome, step-by-step mechanisms have been reconstituted, and some new players identified. This review summarizes the latest developments in the area, focusing on (a) the structure of the replisome and mechanisms of action of its components, (b) organization of replisome transactions and repair, (c) replisome dynamics, and (d) factors influencing the base and sugar fidelity of DNA synthesis.
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Affiliation(s)
- Krystian Łazowski
- Laboratory of DNA Replication and Genome Stability, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland
| | - Roger Woodgate
- Laboratory of Genomic Integrity, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-3371, United States
| | - Iwona J Fijalkowska
- Laboratory of DNA Replication and Genome Stability, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland
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3
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Machitani M, Nomura A, Yamashita T, Yasukawa M, Ueki S, Fujita KI, Ueno T, Yamashita A, Tanzawa Y, Watanabe M, Taniguchi T, Saitoh N, Kaneko S, Kato Y, Mano H, Masutomi K. Maintenance of R-loop structures by phosphorylated hTERT preserves genome integrity. Nat Cell Biol 2024; 26:932-945. [PMID: 38806647 DOI: 10.1038/s41556-024-01427-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 04/23/2024] [Indexed: 05/30/2024]
Abstract
As aberrant accumulation of RNA-DNA hybrids (R-loops) causes DNA damage and genome instability, cells express regulators of R-loop structures. Here we report that RNA-dependent RNA polymerase (RdRP) activity of human telomerase reverse transcriptase (hTERT) regulates R-loop formation. We found that the phosphorylated form of hTERT (p-hTERT) exhibits RdRP activity in nuclear speckles both in telomerase-positive cells and telomerase-negative cells with alternative lengthening of telomeres (ALT) activity. The p-hTERT did not associate with telomerase RNA component in nuclear speckles but, instead, with TERRA RNAs to resolve R-loops. Targeting of the TERT gene in ALT cells ablated RdRP activity and impaired tumour growth. Using a genome-scale CRISPR loss-of-function screen, we identified Fanconi anaemia/BRCA genes as synthetic lethal partners of hTERT RdRP. Inactivation of RdRP and Fanconi anaemia/BRCA genes caused accumulation of R-loop structures and DNA damage. These findings indicate that RdRP activity of p-hTERT guards against genome instability by removing R-loop structures.
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Affiliation(s)
- Mitsuhiro Machitani
- Division of Cancer Stem Cell, National Cancer Center Research Institute, Tokyo, Japan
| | - Akira Nomura
- Division of Cancer Stem Cell, National Cancer Center Research Institute, Tokyo, Japan
- Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, Isehara, Japan
| | - Taro Yamashita
- Department of Gastroenterology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Mami Yasukawa
- Division of Cancer Stem Cell, National Cancer Center Research Institute, Tokyo, Japan
| | - Saori Ueki
- Division of Cancer Stem Cell, National Cancer Center Research Institute, Tokyo, Japan
| | - Ken-Ichi Fujita
- Division of Cancer Stem Cell, National Cancer Center Research Institute, Tokyo, Japan
| | - Toshihide Ueno
- Division of Cellular Signaling, National Cancer Center Research Institute, Tokyo, Japan
| | - Akio Yamashita
- Department of Investigative Medicine, University of the Ryukyus Graduate School of Medicine, Nakagami, Japan
| | - Yoshikazu Tanzawa
- Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, Isehara, Japan
| | - Masahiko Watanabe
- Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, Isehara, Japan
| | - Toshiyasu Taniguchi
- Department of Molecular Life Science, Tokai University School of Medicine, Isehara, Japan
| | - Noriko Saitoh
- Division of Cancer Biology, The Cancer Institute of JFCR, Tokyo, Japan
| | - Shuichi Kaneko
- Department of Gastroenterology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Yukinari Kato
- Department of Antibody Drug Development, Tohoku University Graduate School of Medicine, Sendai, Japan
- Department of Molecular Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hiroyuki Mano
- Division of Cellular Signaling, National Cancer Center Research Institute, Tokyo, Japan
| | - Kenkichi Masutomi
- Division of Cancer Stem Cell, National Cancer Center Research Institute, Tokyo, Japan.
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4
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Li F, Zafar A, Luo L, Denning AM, Gu J, Bennett A, Yuan F, Zhang Y. R-Loops in Genome Instability and Cancer. Cancers (Basel) 2023; 15:4986. [PMID: 37894353 PMCID: PMC10605827 DOI: 10.3390/cancers15204986] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/04/2023] [Accepted: 10/11/2023] [Indexed: 10/29/2023] Open
Abstract
R-loops are unique, three-stranded nucleic acid structures that primarily form when an RNA molecule displaces one DNA strand and anneals to the complementary DNA strand in a double-stranded DNA molecule. R-loop formation can occur during natural processes, such as transcription, in which the nascent RNA molecule remains hybridized with the template DNA strand, while the non-template DNA strand is displaced. However, R-loops can also arise due to many non-natural processes, including DNA damage, dysregulation of RNA degradation pathways, and defects in RNA processing. Despite their prevalence throughout the whole genome, R-loops are predominantly found in actively transcribed gene regions, enabling R-loops to serve seemingly controversial roles. On one hand, the pathological accumulation of R-loops contributes to genome instability, a hallmark of cancer development that plays a role in tumorigenesis, cancer progression, and therapeutic resistance. On the other hand, R-loops play critical roles in regulating essential processes, such as gene expression, chromatin organization, class-switch recombination, mitochondrial DNA replication, and DNA repair. In this review, we summarize discoveries related to the formation, suppression, and removal of R-loops and their influence on genome instability, DNA repair, and oncogenic events. We have also discussed therapeutical opportunities by targeting pathological R-loops.
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Affiliation(s)
- Fang Li
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Alyan Zafar
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Liang Luo
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Ariana Maria Denning
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Jun Gu
- Department of Molecular and Cellular Pharmacology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Ansley Bennett
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Fenghua Yuan
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Yanbin Zhang
- Department of Biochemistry & Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
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5
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Botto MM, Borsellini A, Lamers MH. A four-point molecular handover during Okazaki maturation. Nat Struct Mol Biol 2023; 30:1505-1515. [PMID: 37620586 DOI: 10.1038/s41594-023-01071-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 07/17/2023] [Indexed: 08/26/2023]
Abstract
DNA replication introduces thousands of RNA primers into the lagging strand that need to be removed for replication to be completed. In Escherichia coli when the replicative DNA polymerase Pol IIIα terminates at a previously synthesized RNA primer, DNA Pol I takes over and continues DNA synthesis while displacing the downstream RNA primer. The displaced primer is subsequently excised by an endonuclease, followed by the sealing of the nick by a DNA ligase. Yet how the sequential actions of Pol IIIα, Pol I polymerase, Pol I endonuclease and DNA ligase are coordinated is poorly defined. Here we show that each enzymatic activity prepares the DNA substrate for the next activity, creating an efficient four-point molecular handover. The cryogenic-electron microscopy structure of Pol I bound to a DNA substrate with both an upstream and downstream primer reveals how it displaces the primer in a manner analogous to the monomeric helicases. Moreover, we find that in addition to its flap-directed nuclease activity, the endonuclease domain of Pol I also specifically cuts at the RNA-DNA junction, thus marking the end of the RNA primer and creating a 5' end that is a suitable substrate for the ligase activity of LigA once all RNA has been removed.
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Affiliation(s)
- Margherita M Botto
- Department of Cell and Chemical Biology, Leiden University Medical Center (LUMC), Leiden, the Netherlands
- Department of Molecular and Cellular Biology, Geneva University, Geneva, Switzerland
| | - Alessandro Borsellini
- Department of Cell and Chemical Biology, Leiden University Medical Center (LUMC), Leiden, the Netherlands
- Department of Structural Biology, Human Technopole, Milan, Italy
| | - Meindert H Lamers
- Department of Cell and Chemical Biology, Leiden University Medical Center (LUMC), Leiden, the Netherlands.
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6
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Hao Z, Gowder M, Proshkin S, Bharati BK, Epshtein V, Svetlov V, Shamovsky I, Nudler E. RNA polymerase drives ribonucleotide excision DNA repair in E. coli. Cell 2023; 186:2425-2437.e21. [PMID: 37196657 PMCID: PMC10515295 DOI: 10.1016/j.cell.2023.04.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 11/21/2022] [Accepted: 04/20/2023] [Indexed: 05/19/2023]
Abstract
Ribonuclease HII (RNaseHII) is the principal enzyme that removes misincorporated ribonucleoside monophosphates (rNMPs) from genomic DNA. Here, we present structural, biochemical, and genetic evidence demonstrating that ribonucleotide excision repair (RER) is directly coupled to transcription. Affinity pull-downs and mass-spectrometry-assisted mapping of in cellulo inter-protein cross-linking reveal the majority of RNaseHII molecules interacting with RNA polymerase (RNAP) in E. coli. Cryoelectron microscopy structures of RNaseHII bound to RNAP during elongation, with and without the target rNMP substrate, show specific protein-protein interactions that define the transcription-coupled RER (TC-RER) complex in engaged and unengaged states. The weakening of RNAP-RNaseHII interactions compromises RER in vivo. The structure-functional data support a model where RNaseHII scans DNA in one dimension in search for rNMPs while "riding" the RNAP. We further demonstrate that TC-RER accounts for a significant fraction of repair events, thereby establishing RNAP as a surveillance "vehicle" for detecting the most frequently occurring replication errors.
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Affiliation(s)
- Zhitai Hao
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Manjunath Gowder
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA; Howard Hughes Medical Institute, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Sergey Proshkin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia
| | - Binod K Bharati
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA; Howard Hughes Medical Institute, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Vitaly Epshtein
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Vladimir Svetlov
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Ilya Shamovsky
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Evgeny Nudler
- Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA; Howard Hughes Medical Institute, New York University Grossman School of Medicine, New York, NY 10016, USA.
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7
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Development of an RNase H2 Activity Assay for Clinical Screening. J Clin Med 2023; 12:jcm12041598. [PMID: 36836134 PMCID: PMC9961991 DOI: 10.3390/jcm12041598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/13/2023] [Accepted: 02/14/2023] [Indexed: 02/19/2023] Open
Abstract
As the key enzyme mediating ribonucleotide excision repair, RNase H2 is essential for the removal of single ribonucleotides from DNA in order to prevent genome damage. Loss of RNase H2 activity directly contributes to the pathogenesis of autoinflammatory and autoimmune diseases and might further play a role in ageing and neurodegeneration. Moreover, RNase H2 activity is a potential diagnostic and prognostic marker in several types of cancer. Until today, no method for quantification of RNase H2 activity has been validated for the clinical setting. Herein, validation and benchmarks of a FRET-based whole-cell lysate RNase H2 activity assay are presented, including standard conditions and procedures to calculate standardized RNase H2 activity. Spanning a wide working range, the assay is applicable to various human cell or tissue samples with overall methodological assay variability from 8.6% to 16%. Using our assay, we found RNase H2 activity was reduced in lymphocytes of two patients with systemic lupus erythematosus and one with systemic sclerosis carrying heterozygous mutations in one of the RNASEH2 genes. Implementation of larger control groups will help to assess the diagnostic and prognostic value of clinical screening for RNase H2 activity in the future.
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8
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Pang J, Guo Q, Lu Z. The catalytic mechanism, metal dependence, substrate specificity, and biodiversity of ribonuclease H. Front Microbiol 2022; 13:1034811. [PMID: 36478866 PMCID: PMC9719913 DOI: 10.3389/fmicb.2022.1034811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 10/31/2022] [Indexed: 11/29/2023] Open
Abstract
Ribonucleoside monophosphates are inevitably misincorporated into the DNA genome inside cells, and they need to be excised to avoid chromosome instability. Ribonucleases H (RNases H) are enzymes that specifically hydrolyze the RNA strand of RNA/DNA hybrids or the RNA moiety from DNA containing a stretch of RNA, they therefore are required for DNA integrity. Extensive studies have drawn a mostly clear picture of the mechanisms of RNase H catalysis, but some questions are still lacking definitive answers. This review summarizes three alternative models of RNase H catalysis. The two-metal model is prevalent, but a three-metal model suggests the involvement of a third cation in catalysis. Apparently, the mechanisms underlying metal-dependent hydrolyzation are more complicated than initially thought. We also discuss the metal choices of RNases H and analyze how chemically similar cations function differently. Substrate and cleavage-site specificities vary among RNases H, and this is explicated in detail. An intriguing phenomenon is that organisms have diverse RNase H combinations, which may provide important hints to how rnh genes were transferred during evolution. Whether RNase H is essential for cellular growth, a key question in the study of in vivo functions, is also discussed. This article may aid in understanding the mechanisms underlying RNase H and in developing potentially promising applications of it.
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Affiliation(s)
| | | | - Zheng Lu
- Department of Biology, Guangdong Provincial Key Laboratory of Marine Biotechnology, Institute of Marine Sciences, Shantou University, Shantou, China
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9
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Petermann E, Lan L, Zou L. Sources, resolution and physiological relevance of R-loops and RNA-DNA hybrids. Nat Rev Mol Cell Biol 2022; 23:521-540. [PMID: 35459910 DOI: 10.1038/s41580-022-00474-x] [Citation(s) in RCA: 115] [Impact Index Per Article: 57.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2022] [Indexed: 12/12/2022]
Abstract
RNA-DNA hybrids are generated during transcription, DNA replication and DNA repair and are crucial intermediates in these processes. When RNA-DNA hybrids are stably formed in double-stranded DNA, they displace one of the DNA strands and give rise to a three-stranded structure called an R-loop. R-loops are widespread in the genome and are enriched at active genes. R-loops have important roles in regulating gene expression and chromatin structure, but they also pose a threat to genomic stability, especially during DNA replication. To keep the genome stable, cells have evolved a slew of mechanisms to prevent aberrant R-loop accumulation. Although R-loops can cause DNA damage, they are also induced by DNA damage and act as key intermediates in DNA repair such as in transcription-coupled repair and RNA-templated DNA break repair. When the regulation of R-loops goes awry, pathological R-loops accumulate, which contributes to diseases such as neurodegeneration and cancer. In this Review, we discuss the current understanding of the sources of R-loops and RNA-DNA hybrids, mechanisms that suppress and resolve these structures, the impact of these structures on DNA repair and genome stability, and opportunities to therapeutically target pathological R-loops.
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Affiliation(s)
- Eva Petermann
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
- Birmingham Centre for Genome Biology, University of Birmingham, Birmingham, UK
| | - Li Lan
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, MA, USA
- Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Lee Zou
- Massachusetts General Hospital Cancer Center, Harvard Medical School, Charlestown, MA, USA.
- Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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10
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Kimura N, Takayama KI, Yamada Y, Kume H, Fujimura T, Inoue S. Ribonuclease H2 Subunit A Preserves Genomic Integrity and Promotes Prostate Cancer Progression. CANCER RESEARCH COMMUNICATIONS 2022; 2:870-883. [PMID: 36923313 PMCID: PMC10010380 DOI: 10.1158/2767-9764.crc-22-0126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 06/15/2022] [Accepted: 07/29/2022] [Indexed: 11/16/2022]
Abstract
Homeostasis of genomic integrity should be regulated to promote proliferation and inhibit DNA damage-induced cell death in cancer. Ribonuclease H2 (RNase H2) maintains genome stability by controlling DNA:RNA hybrid and R-loop levels. Here, we identified that RNase H2 subunit A (RNASEH2A), a component of RNase H2, is highly expressed in castration-resistant prostate cancer (CRPC) tissues compared with localized prostate cancer. Interestingly, we showed that RNASEH2A suppressed R-loop levels to prevent cell apoptosis induced by DNA damage in prostate cancer cells. Both in vivo and in vitro studies revealed that RNASEH2A promotes cell growth and migration via the negative regulation of p53 and positive regulation of AR and AR-V7. Mechanistically, epigenetic regulation followed by R-loop accumulation in these promoters was observed for these gene regulations. Importantly, IHC analysis demonstrated that R-loop formation increased in CRPC tissues and correlated with RNASEH2A expression levels. Notably, two small molecules targeting RNase H2 activity were found to suppress CRPC tumor growth with no significant toxic effects. Collectively, we propose that RNASEH2A overexpression is a hallmark of prostate cancer progression by maintaining genomic stability to prevent R-loop-mediated apoptosis induction. Targeting RNase H2 activity could be a potential strategy for treating CRPC tumors. Significance RNASEH2A was demonstrated to be highly upregulated in aggressive prostate cancer to degrade R-loop accumulation and preserve genomic stability for tumor growth, suggesting that RNase H2 activity could be a promising therapeutic target.
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Affiliation(s)
- Naoki Kimura
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.,Department of Urology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Ken-Ichi Takayama
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Yuta Yamada
- Department of Urology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Haruki Kume
- Department of Urology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | | | - Satoshi Inoue
- Department of Systems Aging Science and Medicine, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.,Research Center for Genomic Medicine, Saitama Medical University, Saitama, Japan
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11
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Kandabashi M, Yano H, Hara H, Ogawa S, Kamoda K, Ishibashi S, Himeda K, Baba M, Takita T, Yasukawa K. Analysis of ribonucleotide content in the genomic DNA of ribonuclease H2 A subunit (RH2A)-knockout NIH3T3 cells after transient expression of wild-type RH2A or RH2A variants with an Aicardi-Goutières syndrome-causing mutation. J Biochem 2022; 172:225-231. [DOI: 10.1093/jb/mvac056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 07/03/2022] [Indexed: 11/13/2022] Open
Abstract
Summary
Ribonuclease (RNase) H2 is involved in the removal of ribonucleotides embedded in genomic DNA. Eukaryotic RNase H2 is a heterotrimer consisting of the catalytic A subunit (RH2A) and the accessory B and C subunits. This study aimed to compare the cellular activities of wild-type ribonuclease (RNase) H2 and its variants with a mutation causing neuroinflammatory autoimmune disease, Aicardi-Goutières syndrome (AGS). We first analyzed cellular RNase H2 activity and ribonucleotide content in the genomic DNA of RH2A-knockout (KO) mouse fibroblast NIH3T3 cells after transfection with a transient expression plasmid encoding mouse wild-type RH2A. From four hours after transfection, the RNase H2 activity increased, and the amount of ribonucleotides decreased, as compared with the corresponding non-transfected RH2A-KO cells. This demonstrated the rapidness of ribonucleotide turnover in mammalian genomic DNA and the importance of continuous expression of RNase H2 to maintain the ribonucleotide amount low. Next, we expressed mouse RH2A variants with a mutation corresponding to a human AGS-causing mutation in RH2A-KO NIH3T3 cells. Neither increase in RNase H2 activity nor decrease in ribonucleotide amount were observed for G37S; however, both conditions were observed for N213I and R293H. This corresponded with our previous results on the activity of recombinant human RNase H2 variants.
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Affiliation(s)
- Mako Kandabashi
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Haruna Yano
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Haruka Hara
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Saori Ogawa
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kana Kamoda
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Shu Ishibashi
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kohei Himeda
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Misato Baba
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Teisuke Takita
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kiyoshi Yasukawa
- Graduate School of Agriculture Division of Food Science and Biotechnology, , Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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12
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He D, Guo Y, Cheng J, Wang Y. Chl1 coordinates with H3K9 methyltransferase Clr4 to reduce the accumulation of RNA-DNA hybrids and maintain genome stability. iScience 2022; 25:104313. [PMID: 35602970 PMCID: PMC9118164 DOI: 10.1016/j.isci.2022.104313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 01/30/2022] [Accepted: 04/22/2022] [Indexed: 11/28/2022] Open
Abstract
A genome-wide analysis in Schizosaccharomyces pombe indicated that double-deletion mutants of Chl1 and histone H3K9 methyltransferase complex factors are synthetically sick. Here, we show that loss of Chl1 increases the accumulation of RNA-DNA hybrids at pericentromeric dg and dh repeats in the absence of the H3K9 methyltransferase Clr4, which leads to genome instability, including more severe defects in chromosome segregation and increased chromatin accessibility. Localization of Chl1 at pericentromeric regions depends on a subunit of replication protein A (RPA), Ssb1. In wild-type (WT) cells, transcriptionally repressed heterochromatin prevents the formation of RNA-DNA hybrids. When Clr4 is deleted, dg and dh repeats are highly transcribed. Then Ssb1 associates with the displaced single-stranded DNA (ssDNA) and recruits Chl1 to resolve the RNA-DNA hybrids. Together, our data suggest that Chl1 coordinates with Clr4 to eliminate RNA-DNA hybrids, which contributes to the maintenance of genome integrity. Double mutant of Chl1 and Chl1 leads to the accumulation of RNA-DNA hybrids RNA-DNA hybrids at pericentromeric regions affect genome stability and cell viability Ssb1 recruits Chl1 to unwind RNA-DNA hybrids in the absence of Clr4
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Affiliation(s)
- Deyun He
- College of Biological Sciences, China Agricultural University, Beijing, 100193, China
- College of Bioengineering, Key Laboratory of Shandong Microbial Engineering, State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Shandong Academy of Sciences, Jinan, Shandong 250353, China
| | - Yazhen Guo
- College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Jinkui Cheng
- College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Yu Wang
- College of Biological Sciences, China Agricultural University, Beijing, 100193, China
- Corresponding author
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13
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Jones SP, Goossen C, Lewis SD, Delaney AM, Gleghorn ML. Not making the cut: Techniques to prevent RNA cleavage in structural studies of RNase-RNA complexes. J Struct Biol X 2022; 6:100066. [PMID: 35340590 PMCID: PMC8943300 DOI: 10.1016/j.yjsbx.2022.100066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 11/16/2022] Open
Abstract
RNases are varied in the RNA structures and sequences they target for cleavage and are an important type of enzyme in cells. Despite the numerous examples of RNases known, and of those with determined three-dimensional structures, relatively few examples exist with the RNase bound to intact cognate RNA substrate prior to cleavage. To better understand RNase structure and sequence specificity for RNA targets, in vitro methods used to assemble these enzyme complexes trapped in a pre-cleaved state have been developed for a number of different RNases. We have surveyed the Protein Data Bank for such structures and in this review detail methodologies that have successfully been used and relate them to the corresponding structures. We also offer ideas and suggestions for future method development. Many strategies within this review can be used in combination with X-ray crystallography, as well as cryo-EM, and other structure-solving techniques. Our hope is that this review will be used as a guide to resolve future yet-to-be-determined RNase-substrate complex structures.
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Affiliation(s)
- Seth P. Jones
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
| | - Christian Goossen
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Lothrop St, Pittsburgh, PA 15261, United States
| | - Sean D. Lewis
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
- Mayo Clinic, 200 1st St SW, Rochester, MN 5590, United States
| | - Annie M. Delaney
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
| | - Michael L. Gleghorn
- School of Chemistry and Materials Science, Rochester Institute of Technology, 85 Lomb Memorial Drive, Rochester, NY 14623-5603, United States
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Lee H, Cho H, Kim J, Lee S, Yoo J, Park D, Lee G. RNase H is an exo- and endoribonuclease with asymmetric directionality, depending on the binding mode to the structural variants of RNA:DNA hybrids. Nucleic Acids Res 2022; 50:1801-1814. [PMID: 34788459 PMCID: PMC8886854 DOI: 10.1093/nar/gkab1064] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 10/12/2021] [Accepted: 10/20/2021] [Indexed: 11/22/2022] Open
Abstract
RNase H is involved in fundamental cellular processes and is responsible for removing the short stretch of RNA from Okazaki fragments and the long stretch of RNA from R-loops. Defects in RNase H lead to embryo lethality in mice and Aicardi-Goutieres syndrome in humans, suggesting the importance of RNase H. To date, RNase H is known to be a non-sequence-specific endonuclease, but it is not known whether it performs other functions on the structural variants of RNA:DNA hybrids. Here, we used Escherichia coli RNase H as a model, and examined its catalytic mechanism and its substrate recognition modes, using single-molecule FRET. We discovered that RNase H acts as a processive exoribonuclease on the 3' DNA overhang side but as a distributive non-sequence-specific endonuclease on the 5' DNA overhang side of RNA:DNA hybrids or on blunt-ended hybrids. The high affinity of previously unidentified double-stranded (ds) and single-stranded (ss) DNA junctions flanking RNA:DNA hybrids may help RNase H find the hybrid substrates in long genomic DNA. Our study provides new insights into the multifunctionality of RNase H, elucidating unprecedented roles of junctions and ssDNA overhang on RNA:DNA hybrids.
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Affiliation(s)
- Hyunjee Lee
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
- Single-Molecule Biology Laboratory, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
- Cell Mechanobiology Laboratory, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - HyeokJin Cho
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
- Single-Molecule Biology Laboratory, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
- Cell Mechanobiology Laboratory, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - Jooyoung Kim
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - Sua Lee
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - Jungmin Yoo
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
- Single-Molecule Biology Laboratory, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
- Cell Mechanobiology Laboratory, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - Daeho Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
- Cell Mechanobiology Laboratory, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
| | - Gwangrog Lee
- School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
- Single-Molecule Biology Laboratory, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
- Cell Mechanobiology Laboratory, Gwangju Institute of Science and Technology, Gwangju 61005, Korea
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15
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Zhao F, Liu A, Gong X, Chen H, Wei J, Chen B, Chen S, Yang R, Fan Y, Mao R. Hypoxia-induced RNASEH2A limits activation of cGAS-STING signaling in HCC and predicts poor prognosis. TUMORI JOURNAL 2021; 108:63-76. [PMID: 34165025 DOI: 10.1177/03008916211026019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Hypoxia is a hallmark of solid cancers, including hepatocellular carcinoma (HCC). There is scarce information about how hypoxia avoids immunologic stress and maintains a cancer-promoting microenvironment. METHODS The Cancer Genome Atlas, RNA-seq data, and Oncomine database were used to discover the correlation of RNASEH2A with tumor progression; then expression of RNASEH2A mRNA and protein were detected in HCC tissues and cells subjected to hypoxia or with the treatment of CoCl2 via real-time quantitative polymerase chain reaction and immunochemistry assays. Finally, the effect of RNASEH2A on cell proliferation and the involved signaling pathway was explored further. RESULTS RNASEH2A was positively correlated with tumor grade, size, vascular invasion, and poor prognosis. The expression of RNASEH2A mRNA and protein were increased and dependent on hypoxia-inducible factor 2α in HCC tissues and cell lines. Knockout of RNASEH2A in HCC cells greatly reduced cell proliferation and induced the transcription of multiple cGAS-STING (cyclic GMP-AMP synthase-stimulator of interferon genes) targeted type 1 interferon-related genes, including IFIT1, USP18, and CXCL10, which suggests knockout of RNASEH2A may produce immunologic stress and tumor suppressive effects. CONCLUSIONS RNASEH2A plays a critical role and potentially predicts patient outcomes in HCC, which uncovers a new mechanism that RNASEH2A contributes to limit immunologic stress of cancer cells in the context of hypoxia.
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Affiliation(s)
- Fengbo Zhao
- Laboratory of Medical Science, School of Medicine, Nantong University, Jiangsu, China
| | - Aifen Liu
- Laboratory of Medical Science, School of Medicine, Nantong University, Jiangsu, China
| | - Xiu Gong
- Laboratory of Medical Science, School of Medicine, Nantong University, Jiangsu, China
| | - Hao Chen
- Department of Gastroenterology, Affiliated Hospital of Nantong University, Jiangsu, China
| | - Jinhuan Wei
- Laboratory of Medical Science, School of Medicine, Nantong University, Jiangsu, China
| | - Bin Chen
- Laboratory of Medical Science, School of Medicine, Nantong University, Jiangsu, China
| | - Shiyin Chen
- Laboratory of Medical Science, School of Medicine, Nantong University, Jiangsu, China
| | - Riyun Yang
- Laboratory of Medical Science, School of Medicine, Nantong University, Jiangsu, China
| | - Yihui Fan
- Laboratory of Medical Science, School of Medicine, Nantong University, Jiangsu, China.,Department of Pathogen Biology, School of Medicine, Nantong University, Jiangsu, China
| | - Renfang Mao
- Laboratory of Medical Science, School of Medicine, Nantong University, Jiangsu, China.,Department of Pathophysiology, School of Medicine, Nantong University, Jiangsu, China
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16
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High Flexibility of RNaseH2 Catalytic Activity with Respect to Non-Canonical DNA Structures. Int J Mol Sci 2021; 22:ijms22105201. [PMID: 34068992 PMCID: PMC8155979 DOI: 10.3390/ijms22105201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 11/17/2022] Open
Abstract
Ribonucleotides misincorporated in the human genome are the most abundant DNA lesions. The 2'-hydroxyl group makes them prone to spontaneous hydrolysis, potentially resulting in strand breaks. Moreover, their presence may decrease the rate of DNA replication causing replicative fork stalling and collapse. Ribonucleotide removal is initiated by Ribonuclease H2 (RNase H2), the key player in Ribonucleotide Excision Repair (RER). Its absence leads to embryonic lethality in mice, while mutations decreasing its activity cause Aicardi-Goutières syndrome. DNA geometry can be altered by DNA lesions or by peculiar sequences forming secondary structures, like G-quadruplex (G4) and trinucleotide repeats (TNR) hairpins, which significantly differ from canonical B-form. Ribonucleotides pairing to lesioned nucleotides, or incorporated within non-B DNA structures could avoid RNase H2 recognition, potentially contributing to genome instability. In this work, we investigate the ability of RNase H2 to process misincorporated ribonucleotides in a panel of DNA substrates showing different geometrical features. RNase H2 proved to be a flexible enzyme, recognizing as a substrate the majority of the constructs we generated. However, some geometrical features and non-canonical DNA structures severely impaired its activity, suggesting a relevant role of misincorporated ribonucleotides in the physiological instability of specific DNA sequences.
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Abstract
The type I interferonopathies comprise a heterogenous group of monogenic diseases associated with a constitutive activation of type I interferon signaling.The elucidation of the genetic causes of this group of diseases revealed an alteration of nucleic acid processing and signaling.ADAR1 is among the genes found mutated in patients with this type of disorders.This enzyme catalyzes the hydrolytic deamination of adenosines in inosines within a double-stranded RNA target (RNA editing of A to I). This RNA modification is widespread in human cells and deregulated in a variety of human diseases, ranging from cancers to neurological abnormalities.In this review, we briefly summarize the knowledge about the RNA editing alterations occurring in patients with mutations in ADAR1 gene and how these alterations might cause the inappropriate IFN activation.
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Affiliation(s)
- Loredana Frassinelli
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
| | - Silvia Galardi
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
| | - Silvia Anna Ciafrè
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy
| | - Alessandro Michienzi
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, Rome, Italy.
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18
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Colombo CV, Gnugnoli M, Gobbini E, Longhese MP. How do cells sense DNA lesions? Biochem Soc Trans 2020; 48:677-691. [PMID: 32219379 DOI: 10.1042/bst20191118] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 03/06/2020] [Accepted: 03/12/2020] [Indexed: 12/17/2023]
Abstract
DNA is exposed to both endogenous and exogenous DNA damaging agents that chemically modify it. To counteract the deleterious effects exerted by DNA lesions, eukaryotic cells have evolved a network of cellular pathways, termed DNA damage response (DDR). The DDR comprises both mechanisms devoted to repair DNA lesions and signal transduction pathways that sense DNA damage and transduce this information to specific cellular targets. These targets, in turn, impact a wide range of cellular processes including DNA replication, DNA repair and cell cycle transitions. The importance of the DDR is highlighted by the fact that DDR inactivation is commonly found in cancer and causes many different human diseases. The protein kinases ATM and ATR, as well as their budding yeast orthologs Tel1 and Mec1, act as master regulators of the DDR. The initiating events in the DDR entail both DNA lesion recognition and assembly of protein complexes at the damaged DNA sites. Here, we review what is known about the early steps of the DDR.
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Affiliation(s)
- Chiara Vittoria Colombo
- Dipartimento di Biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
| | - Marco Gnugnoli
- Dipartimento di Biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
| | - Elisa Gobbini
- Dipartimento di Biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
| | - Maria Pia Longhese
- Dipartimento di Biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca, Piazza della Scienza 2, 20126 Milano, Italy
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19
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Baba M, Kojima K, Nishimura T, Sugiura T, Takita T, Uehara R, Crouch RJ, Yasukawa K. Val143 of human ribonuclease H2 is not critical for, but plays a role in determining catalytic activity and substrate specificity. PLoS One 2020; 15:e0228774. [PMID: 32069311 PMCID: PMC7028304 DOI: 10.1371/journal.pone.0228774] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 01/22/2020] [Indexed: 11/18/2022] Open
Abstract
Ribonuclease H2 (RNase H2) exhibits both single ribonucleotide excision activity (activity A) and RNA strand degrading activity (activity B). Val143 of human RNase H2 is located at the active site and is conserved in eukaryotic RNase H2. In this study, we explored the role of Val143 in catalytic activity and substrate specificity. Nineteen single variants at amino acid position 143 were expressed in E. coli, and all variants except for V143C and V143M were purified from the cells. When the activity of the wild-type human RNase H2 (WT) was set as 100%, the relative activities A and B of the 17 variants were in the range of 0.05–130 and 0.02–42%, respectively. When the ratio of the relative activity A to the relative activity B of WT was set as 1, the ratios of the 17 variants were in the range of 0.2–5.7. This indicates that valine is optimal for balancing the two activities. The ratios for V143Y and V143W were relatively high (5.6 and 5.5, respectively), suggesting that the bulky residues like tyrosine and tryptophan at position 143 caused steric hindrance with the 2’-OH of the sugar moiety of the ribonucleotide at the 5’ side of the scissile phosphodiester bond. The ratio for V143Q was relatively low (0.2). These results suggested that Val143 is not critical for, but plays a role in determining catalytic activity and substrate specificity.
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Affiliation(s)
- Misato Baba
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Kenji Kojima
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Takuto Nishimura
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Takuya Sugiura
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Teisuke Takita
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Ryo Uehara
- Section on Formation of RNA, Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States of America
- Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, Noji-higashi, Shiga, Japan
| | - Robert J. Crouch
- Section on Formation of RNA, Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, United States of America
| | - Kiyoshi Yasukawa
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan
- * E-mail:
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20
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Li Q, Chen J, Trajkovski M, Zhou Y, Fan C, Lu K, Tang P, Su X, Plavec J, Xi Z, Zhou C. 4′-Fluorinated RNA: Synthesis, Structure, and Applications as a Sensitive 19F NMR Probe of RNA Structure and Function. J Am Chem Soc 2020; 142:4739-4748. [DOI: 10.1021/jacs.9b13207] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Qiang Li
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jialiang Chen
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Marko Trajkovski
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia
- University of Ljubljana, Faculty of Chemistry and Chemical Technology, Ljubljana, EN-FIST Centre of Excellence, Ljubljana, Slovenia
| | - Yifei Zhou
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Chaochao Fan
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Kuan Lu
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Pingping Tang
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xuncheng Su
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, Ljubljana, Slovenia
- University of Ljubljana, Faculty of Chemistry and Chemical Technology, Ljubljana, EN-FIST Centre of Excellence, Ljubljana, Slovenia
| | - Zhen Xi
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Chuanzheng Zhou
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, Nankai University, Tianjin 300071, China
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21
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Kellner V, Luke B. Molecular and physiological consequences of faulty eukaryotic ribonucleotide excision repair. EMBO J 2020; 39:e102309. [PMID: 31833079 PMCID: PMC6996501 DOI: 10.15252/embj.2019102309] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 10/22/2019] [Accepted: 11/26/2019] [Indexed: 01/11/2023] Open
Abstract
The duplication of the eukaryotic genome is an intricate process that has to be tightly safe-guarded. One of the most frequently occurring errors during DNA synthesis is the mis-insertion of a ribonucleotide instead of a deoxyribonucleotide. Ribonucleotide excision repair (RER) is initiated by RNase H2 and results in error-free removal of such mis-incorporated ribonucleotides. If left unrepaired, DNA-embedded ribonucleotides result in a variety of alterations within chromosomal DNA, which ultimately lead to genome instability. Here, we review how genomic ribonucleotides lead to chromosomal aberrations and discuss how the tight regulation of RER timing may be important for preventing unwanted DNA damage. We describe the structural impact of unrepaired ribonucleotides on DNA and chromatin and comment on the potential consequences for cellular fitness. In the context of the molecular mechanisms associated with faulty RER, we have placed an emphasis on how and why increased levels of genomic ribonucleotides are associated with severe autoimmune syndromes, neuropathology, and cancer. In addition, we discuss therapeutic directions that could be followed for pathologies associated with defective removal of ribonucleotides from double-stranded DNA.
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Affiliation(s)
- Vanessa Kellner
- Institute of Molecular Biology (IMB)MainzGermany
- Present address:
Department of BiologyNew York UniversityNew YorkNYUSA
| | - Brian Luke
- Institute of Molecular Biology (IMB)MainzGermany
- Institute of Developmental Biology and Neurobiology (IDN)Johannes Gutenberg UniversitätMainzGermany
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22
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Oo A, Kim DH, Schinazi RF, Kim B. Viral protein X reduces the incorporation of mutagenic noncanonical rNTPs during lentivirus reverse transcription in macrophages. J Biol Chem 2020; 295:657-666. [PMID: 31806704 PMCID: PMC6956541 DOI: 10.1074/jbc.ra119.011466] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 12/02/2019] [Indexed: 11/21/2022] Open
Abstract
Unlike activated CD4+ T cells, nondividing macrophages have an extremely small dNTP pool, which restricts HIV-1 reverse transcription. However, rNTPs are equally abundant in both of these cell types and reach much higher concentrations than dNTPs. The greater difference in concentration between dNTPs and rNTPs in macrophages results in frequent misincorporation of noncanonical rNTPs during HIV-1 reverse transcription. Here, we tested whether the highly abundant SAM domain- and HD domain-containing protein 1 (SAMHD1) deoxynucleoside triphosphorylase in macrophages is responsible for frequent rNTP incorporation during HIV-1 reverse transcription. We also assessed whether Vpx (viral protein X), an accessory protein of HIV-2 and some simian immunodeficiency virus strains that targets SAMHD1 for proteolytic degradation, can counteract the rNTP incorporation. Results from biochemical simulation of HIV-1 reverse transcriptase-mediated DNA synthesis confirmed that rNTP incorporation is reduced under Vpx-mediated dNTP elevation. Using HIV-1 vector, we further demonstrated that dNTP pool elevation by Vpx or deoxynucleosides in human primary monocyte-derived macrophages reduces noncanonical rNTP incorporation during HIV-1 reverse transcription, an outcome similarly observed with the infectious HIV-1 89.6 strain. Furthermore, the simian immunodeficiency virus mac239 strain, encoding Vpx, displayed a much lower level of rNTP incorporation than its ΔVpx mutant in macrophages. Finally, the amount of rNMPs incorporated in HIV-1 proviral DNAs remained unchanged for ∼2 weeks in macrophages. These findings suggest that noncanonical rNTP incorporation is regulated by SAMHD1 in macrophages, whereas rNMPs incorporated in HIV-1 proviral DNA remain unrepaired. This suggests a potential long-term DNA damage impact of SAMHD1-mediated rNTP incorporation in macrophages.
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Affiliation(s)
- Adrian Oo
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia 30322
| | - Dong-Hyun Kim
- Department of Pharmacy, Kyung Hee University, Seoul 02447, South Korea
| | - Raymond F Schinazi
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia 30322
| | - Baek Kim
- Department of Pediatrics, School of Medicine, Emory University, Atlanta, Georgia 30322; Center for Drug Discovery, Children's Healthcare of Atlanta, Atlanta, Georgia 30322.
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23
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Cerritelli SM, Crouch RJ. RNase H2-RED carpets the path to eukaryotic RNase H2 functions. DNA Repair (Amst) 2019; 84:102736. [PMID: 31761672 PMCID: PMC6936605 DOI: 10.1016/j.dnarep.2019.102736] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 10/15/2019] [Indexed: 11/24/2022]
Abstract
Eukaryotic RNases H2 have dual functions in initiating the removal of ribonucleoside monophosphates (rNMPs) incorporated by DNA polymerases during DNA synthesis and in cleaving the RNA moiety of RNA/DNA hybrids formed during transcription and retrotransposition. The other major cellular RNase H, RNase H1, shares the hybrid processing activity, but not all substrates. After RNase H2 incision at the rNMPs in DNA the Ribonucleotide Excision Repair (RER) pathway completes the removal, restoring dsDNA. The development of the RNase H2-RED (Ribonucleotide Excision Defective) mutant enzyme, which can process RNA/DNA hybrids but is unable to cleave rNMPs embedded in DNA has unlinked the two activities and illuminated the roles of RNase H2 in cellular metabolism. Studies mostly in Saccharomyces cerevisiae, have shown both activities of RNase H2 are necessary to maintain genome integrity and that RNase H1 and H2 have overlapping as well as distinct RNA/DNA hybrid substrates. In mouse RNase H2-RED confirmed that rNMPs in DNA during embryogenesis induce lethality in a p53-dependent DNA damage response. In mammalian cell cultures, RNase H2-RED helped identifying DNA lesions produced by Top1 cleavage at rNMPs and led to determine that RNase H2 participates in the retrotransposition of LINE-1 elements. In this review, we summarize the studies and conclusions reached by utilization of RNase H2-RED enzyme in different model systems.
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Affiliation(s)
- Susana M Cerritelli
- SFR, Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Robert J Crouch
- SFR, Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
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24
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Lietard J, Damha MJ, Somoza MM. Large-Scale Photolithographic Synthesis of Chimeric DNA/RNA Hairpin Microarrays To Explore Sequence Specificity Landscapes of RNase HII Cleavage. Biochemistry 2019; 58:4389-4397. [PMID: 31631649 PMCID: PMC6838787 DOI: 10.1021/acs.biochem.9b00806] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Ribonuclease HII (RNase HII) is an essential endoribonuclease that binds to double-stranded DNA with RNA nucleotide incorporations and cleaves 5' of the ribonucleotide at RNA-DNA junctions. Thought to be present in all domains of life, RNase HII protects genomic integrity by initiating excision repair pathways that protect the encoded information from rapid degradation. There is sparse evidence that the enzyme cleaves some substrates better than others, but a large-scale study is missing. Such large-scale studies can be carried out on microarrays, and we employ chemical photolithography to synthesize very large combinatorial libraries of fluorescently labeled DNA/RNA chimeric sequences that self-anneal to form hairpin structures that are substrates for Escherichia coli RNase HII. The relative activity is determined by the loss of fluorescence upon cleavage. Each substrate includes a double-stranded 5 bp variable region with one to five consecutive ribonucleotide substitutions. We also examined the effect of all possible single and double mismatches, for a total of >9500 unique structures. Differences in cleavage efficiency indicate some level of substrate preference, and we identified the 5'-dC/rC-rA-dX-3' motif in well-cleaved substrates. The results significantly extend known patterns of RNase HII sequence specificity and serve as a template using large-scale photolithographic synthesis to comprehensively map landscapes of substrate specificity of nucleic acid-processing enzymes.
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Affiliation(s)
- Jory Lietard
- Institute of Inorganic Chemistry, Faculty of Chemistry , University of Vienna , Althanstraße 14 (UZA II) , 1090 Vienna , Austria
| | - Masad J Damha
- Department of Chemistry , McGill University , 801 Rue Sherbrooke Ouest , Montreal , QC H3A 0B8 , Canada
| | - Mark M Somoza
- Institute of Inorganic Chemistry, Faculty of Chemistry , University of Vienna , Althanstraße 14 (UZA II) , 1090 Vienna , Austria
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25
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Górecka KM, Krepl M, Szlachcic A, Poznański J, Šponer J, Nowotny M. RuvC uses dynamic probing of the Holliday junction to achieve sequence specificity and efficient resolution. Nat Commun 2019; 10:4102. [PMID: 31506434 PMCID: PMC6736871 DOI: 10.1038/s41467-019-11900-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 08/09/2019] [Indexed: 12/31/2022] Open
Abstract
Holliday junctions (HJs) are four-way DNA structures that occur in DNA repair by homologous recombination. Specialized nucleases, termed resolvases, remove (i.e., resolve) HJs. The bacterial protein RuvC is a canonical resolvase that introduces two symmetric cuts into the HJ. For complete resolution of the HJ, the two cuts need to be tightly coordinated. They are also specific for cognate DNA sequences. Using a combination of structural biology, biochemistry, and a computational approach, here we show that correct positioning of the substrate for cleavage requires conformational changes within the bound DNA. These changes involve rare high-energy states with protein-assisted base flipping that are readily accessible for the cognate DNA sequence but not for non-cognate sequences. These conformational changes and the relief of protein-induced structural tension of the DNA facilitate coordination between the two cuts. The unique DNA cleavage mechanism of RuvC demonstrates the importance of high-energy conformational states in nucleic acid readouts.
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Affiliation(s)
- Karolina Maria Górecka
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, 4 Trojdena St., 02-109, Warsaw, Poland
| | - Miroslav Krepl
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65, Brno, Czech Republic.
| | - Aleksandra Szlachcic
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, 4 Trojdena St., 02-109, Warsaw, Poland
| | - Jarosław Poznański
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, 5a Pawinskiego St., 02-106, Warsaw, Poland
| | - Jiří Šponer
- Institute of Biophysics of the Czech Academy of Sciences, Kralovopolska 135, 612 65, Brno, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Faculty of Science, Palacky University Olomouc, Slechtitelu 27, 771 46, Olomouc, Czech Republic
| | - Marcin Nowotny
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, 4 Trojdena St., 02-109, Warsaw, Poland.
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26
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Hyjek M, Figiel M, Nowotny M. RNases H: Structure and mechanism. DNA Repair (Amst) 2019; 84:102672. [PMID: 31371183 DOI: 10.1016/j.dnarep.2019.102672] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 07/05/2019] [Accepted: 07/12/2019] [Indexed: 12/11/2022]
Abstract
RNases H are a family of endonucleases that hydrolyze RNA residues in various nucleic acids. These enzymes are present in all branches of life, and their counterpart domains are also found in reverse transcriptases (RTs) from retroviruses and retroelements. RNases H are divided into two main classes (RNases H1 and H2 or type 1 and type 2 enzymes) with common structural features of the catalytic domain but different range of substrates for enzymatic cleavage. Additionally, a third class is found in some Archaea and bacteria. Besides distinct cellular functions specific for each type of RNases H, this family of proteins is generally involved in the maintenance of genome stability with overlapping and cooperative role in removal of R-loops thus preventing their accumulation. Extensive biochemical and structural studies of RNases H provided not only a comprehensive and complete picture of their mechanism but also revealed key basic principles of nucleic acid recognition and processing. RNase H1 is present in prokaryotes and eukaryotes and cleaves RNA in RNA/DNA hybrids. Its main function is hybrid removal, notably in the context of R-loops. RNase H2, which is also present in all branches of life, can play a similar role but it also has a specialized function in the cleavage of single ribonucleotides embedded in the DNA. RNase H3 is present in Archaea and bacteria and is closely related to RNase H2 in sequence and structure but has RNase H1-like biochemical properties. This review summarizes the mechanisms of substrate recognition and enzymatic cleavage by different classes of RNases H with particular insights into structural features of nucleic acid binding, specificity towards RNA and/or DNA strands and catalysis.
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Affiliation(s)
- Malwina Hyjek
- ProBiostructures, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw, 02-109, Poland.
| | - Małgorzata Figiel
- Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw, 02-109, Poland.
| | - Marcin Nowotny
- ProBiostructures, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw, 02-109, Poland; Laboratory of Protein Structure, International Institute of Molecular and Cell Biology, Trojdena 4, Warsaw, 02-109, Poland.
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27
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Choi J, Hwang SY, Ahn K. Interplay between RNASEH2 and MOV10 controls LINE-1 retrotransposition. Nucleic Acids Res 2019; 46:1912-1926. [PMID: 29315404 PMCID: PMC5829647 DOI: 10.1093/nar/gkx1312] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 12/23/2017] [Indexed: 01/22/2023] Open
Abstract
Long interspersed nuclear element 1 is an autonomous non-long terminal repeat retrotransposon that comprises ∼17% of the human genome. Its spontaneous retrotransposition and the accumulation of heritable L1 insertions can potentially result in genome instability and sporadic disorders. Moloney leukemia virus 10 homolog (MOV10), a putative RNA helicase, has been implicated in inhibiting L1 replication, although its underlying mechanism of action remains obscure. Moreover, the physiological relevance of MOV10-mediated L1 regulation in human disease has not yet been examined. Using a proteomic approach, we identified RNASEH2 as a binding partner of MOV10. We show that MOV10 interacts with RNASEH2, and their interplay is crucial for restricting L1 retrotransposition. RNASEH2 and MOV10 co-localize in the nucleus, and RNASEH2 binds to L1 RNAs in a MOV10-dependent manner. Small hairpin RNA-mediated depletion of either RNASEH2A or MOV10 results in an accumulation of L1-specific RNA-DNA hybrids, suggesting they contribute to prevent formation of vital L1 heteroduplexes during retrotransposition. Furthermore, we show that RNASEH2-MOV10-mediated L1 restriction downregulates expression of the rheumatoid arthritis-associated inflammatory cytokines and matrix-degrading proteinases in synovial cells, implicating a potential causal relationship between them and disease development in terms of disease predisposition.
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Affiliation(s)
- Jongsu Choi
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Republic of Korea.,School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Sung-Yeon Hwang
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Republic of Korea.,School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Kwangseog Ahn
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Republic of Korea.,School of Biological Sciences, Seoul National University, Seoul 08826, Republic of Korea
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28
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Malfatti MC, Henneke G, Balachander S, Koh KD, Newnam G, Uehara R, Crouch RJ, Storici F, Tell G. Unlike the Escherichia coli counterpart, archaeal RNase HII cannot process ribose monophosphate abasic sites and oxidized ribonucleotides embedded in DNA. J Biol Chem 2019; 294:13061-13072. [PMID: 31300556 DOI: 10.1074/jbc.ra119.009493] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 07/05/2019] [Indexed: 12/12/2022] Open
Abstract
The presence of ribonucleoside monophosphates (rNMPs) in nuclear DNA decreases genome stability. To ensure survival despite rNMP insertions, cells have evolved a complex network of DNA repair mechanisms, in which the ribonucleotide excision repair pathway, initiated by type 2 RNase H (RNase HII/2), plays a major role. We recently demonstrated that eukaryotic RNase H2 cannot repair damage, that is, ribose monophosphate abasic (both apurinic or apyrimidinic) site (rAP) or oxidized rNMP embedded in DNA. Currently, it remains unclear why RNase H2 is unable to repair these modified nucleic acids having either only a sugar moiety or an oxidized base. Here, we compared the endoribonuclease specificity of the RNase HII enzymes from the archaeon Pyrococcus abyssi and the bacterium Escherichia coli, examining their ability to process damaged rNMPs embedded in DNA in vitro We found that E. coli RNase HII cleaves both rAP and oxidized rNMP sites. In contrast, like the eukaryotic RNase H2, P. abyssi RNase HII did not display any rAP or oxidized rNMP incision activities, even though it recognized them. Notably, the archaeal enzyme was also inactive on a mismatched rNMP, whereas the E. coli enzyme displayed a strong preference for the mispaired rNMP over the paired rNMP in DNA. On the basis of our biochemical findings and also structural modeling analyses of RNase HII/2 proteins from organisms belonging to all three domains of life, we propose that RNases HII/2's dual roles in ribonucleotide excision repair and RNA/DNA hydrolysis result in limited acceptance of modified rNMPs embedded in DNA.
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Affiliation(s)
- Matilde Clarissa Malfatti
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, 33100 Udine, Italy
| | - Ghislaine Henneke
- Ifremer, Univ Brest, CNRS, Laboratoire de Microbiologie des Environnements Extrêmes, F-29280 Plouzané, France
| | - Sathya Balachander
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Kyung Duk Koh
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Gary Newnam
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Ryo Uehara
- Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, 1-1-1 Noji-higashi, Kusatsu, Shiga 525-8577, Japan
| | - Robert J Crouch
- Division of Intramural Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892
| | - Francesca Storici
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Gianluca Tell
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, 33100 Udine, Italy.
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29
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Bechhofer DH, Deutscher MP. Bacterial ribonucleases and their roles in RNA metabolism. Crit Rev Biochem Mol Biol 2019; 54:242-300. [PMID: 31464530 PMCID: PMC6776250 DOI: 10.1080/10409238.2019.1651816] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/22/2019] [Accepted: 07/31/2019] [Indexed: 12/16/2022]
Abstract
Ribonucleases (RNases) are mediators in most reactions of RNA metabolism. In recent years, there has been a surge of new information about RNases and the roles they play in cell physiology. In this review, a detailed description of bacterial RNases is presented, focusing primarily on those from Escherichia coli and Bacillus subtilis, the model Gram-negative and Gram-positive organisms, from which most of our current knowledge has been derived. Information from other organisms is also included, where relevant. In an extensive catalog of the known bacterial RNases, their structure, mechanism of action, physiological roles, genetics, and possible regulation are described. The RNase complement of E. coli and B. subtilis is compared, emphasizing the similarities, but especially the differences, between the two. Included are figures showing the three major RNA metabolic pathways in E. coli and B. subtilis and highlighting specific steps in each of the pathways catalyzed by the different RNases. This compilation of the currently available knowledge about bacterial RNases will be a useful tool for workers in the RNA field and for others interested in learning about this area.
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Affiliation(s)
- David H. Bechhofer
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Murray P. Deutscher
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, USA
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30
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Tsukiashi M, Baba M, Kojima K, Himeda K, Takita T, Yasukawa K. Construction and characterization of ribonuclease H2 knockout NIH3T3 cells. J Biochem 2019; 165:249-256. [PMID: 30481312 DOI: 10.1093/jb/mvy101] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 11/13/2018] [Indexed: 11/13/2022] Open
Abstract
Ribonuclease H (RNase H) specifically hydrolyzes the 5'-phosphodiester bonds of the RNA of RNA/DNA hybrid. Both types 1 and 2 RNases H act on the RNA strand of the hybrid, while only type 2 acts on the single ribonucleotide embedded in DNA duplex. In this study, to explore the role of mammalian type 2 RNase H (RNase H2) in cells, we constructed the RNase H2 knockout NIH3T3 cells (KO cells) by CRISPR/Cas9 system. KO cells hydrolyzed RNA strands in RNA/DNA hybrid, but not single ribonucleotides in DNA duplex, while wild-type NIH3T3 cells (WT cells) hydrolyzed both. Genomic DNA in the KO cells was more heavily hydrolyzed than in the WT cells by the alkaline or RNase H2 treatment, suggesting that the KO cells contained more ribonucleotides in genomic DNA than the WT cells. The growth rate of the KO cells was 60% of that of the WT cells. Expression of interferon-stimulated genes (ISGs) in the KO cells was not markedly elevated compared with the WT cells. These results suggest that in NIH3T3 cells, RNase H2 is crucial for suppressing the accumulation of ribonucleotides in genomic DNA but not for the expression of ISGs.
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Affiliation(s)
- Motoki Tsukiashi
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Misato Baba
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Kenji Kojima
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Kohei Himeda
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Teisuke Takita
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Kiyoshi Yasukawa
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto, Japan
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31
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Fu I, Smith DJ, Broyde S. Rotational and translational positions determine the structural and dynamic impact of a single ribonucleotide incorporated in the nucleosome. DNA Repair (Amst) 2018; 73:155-163. [PMID: 30522887 DOI: 10.1016/j.dnarep.2018.11.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 11/26/2018] [Accepted: 11/28/2018] [Indexed: 12/13/2022]
Abstract
Ribonucleotides misincorporated by replicative DNA polymerases are by far the most common DNA lesion. The presence of ribonucleotides in DNA is associated with genome instability, causing replication stress, chromosome fragility, gross chromosomal rearrangements, and other mutagenic events. Furthermore, nucleosome and chromatin assembly as well as nucleosome positioning are affected by the presence of ribonucleotides. Notably, nucleosome formation is significantly reduced by a single ribonucleotide. Single ribonucleotides are primarily removed from DNA by the ribonucleotide excision repair (RER) pathway via the RNase H2 enzyme, which incises the DNA backbone on the 5'-side of the ribonucleotide. While the structural implications of a single ribonucleotide in free duplex DNA have been well studied, how a single ribonucleotide embedded in nucleosomal DNA impacts nucleosome structure and dynamics, and the possible consequent impact on RER, have not been explored. We have carried out 3.5 μs molecular dynamics simulations of a single ribonucleotide incorporated at various translational and rotational positions in a nucleosome core particle. We find that the presence of the 2'-OH group on the ribose impacts the local conformation and dynamics of both the ribonucleotide and nearby DNA nucleotides as well as their interactions with histones; the nature of these disturbances depends on the rotational and translational setting, including whether the ribose faces toward or away from the histones. The ribonucleotide's preferred C3'-endo pucker is stabilized by interactions with the histones, and furthermore the ribonucleotide can cause dynamic local duplex disturbance involving an abnormal C3'-endo population of the adjacent deoxyribose pucker, minor groove opening, ruptured Watson-Crick pairing, and duplex unwinding that are governed by translation-dependent histone-nucleotide interactions. Possible effects of these disturbances on RER are considered.
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Affiliation(s)
- Iwen Fu
- Department of Biology, New York University, 100 Washington Square East, New York, NY, 10003, United States.
| | - Duncan J Smith
- Department of Biology, New York University, 100 Washington Square East, New York, NY, 10003, United States.
| | - Suse Broyde
- Department of Biology, New York University, 100 Washington Square East, New York, NY, 10003, United States.
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32
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Lietard J, Ameur D, Damha MJ, Somoza MM. High-Density RNA Microarrays Synthesized In Situ by Photolithography. Angew Chem Int Ed Engl 2018; 57:15257-15261. [PMID: 30187993 PMCID: PMC6237118 DOI: 10.1002/anie.201806895] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Indexed: 02/03/2023]
Abstract
While high-density DNA microarrays have been available for over three decades, the synthesis of equivalent RNA microarrays has proven intractable until now. Herein we describe the first in situ synthesis of mixed-based, high-density RNA microarrays using photolithography and light-sensitive RNA phosphoramidites. With coupling efficiencies comparable to those of DNA monomers, RNA oligonucleotides at least 30 nucleotides long can now efficiently be prepared using modified phosphoramidite chemistry. A two-step deprotection route unmasks the phosphodiester, the exocyclic amines and the 2' hydroxyl. Hybridization and enzymatic assays validate the quality and the identity of the surface-bound RNA. We show that high-density is feasible by synthesizing a complex RNA permutation library with 262144 unique sequences. We also introduce DNA/RNA chimeric microarrays and explore their applications by mapping the sequence specificity of RNase HII.
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Affiliation(s)
- Jory Lietard
- Institute of Inorganic ChemistryFaculty of ChemistryUniversity of ViennaAlthanstraße 14, UZA II1090ViennaAustria
| | - Dominik Ameur
- Institute of Inorganic ChemistryFaculty of ChemistryUniversity of ViennaAlthanstraße 14, UZA II1090ViennaAustria
| | - Masad J. Damha
- Department of ChemistryMcGill University801 Rue Sherbrooke OMontréalQC H3A 0B8Canada
| | - Mark M. Somoza
- Institute of Inorganic ChemistryFaculty of ChemistryUniversity of ViennaAlthanstraße 14, UZA II1090ViennaAustria
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33
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Lietard J, Ameur D, Damha MJ, Somoza MM. In‐situ‐Synthese von hochdichten RNA‐Mikroarrays mittels Photolithographie. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201806895] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Jory Lietard
- Institute für Anorganische ChemieFakultät für ChemieUniversität Wien Althanstraße 14, UZA II 1090 Wien Österreich
| | - Dominik Ameur
- Institute für Anorganische ChemieFakultät für ChemieUniversität Wien Althanstraße 14, UZA II 1090 Wien Österreich
| | - Masad J. Damha
- Department of ChemistryMcGill University 801 Rue Sherbrooke O Montréal QC H3A 0B8 Kanada
| | - Mark M. Somoza
- Institute für Anorganische ChemieFakultät für ChemieUniversität Wien Althanstraße 14, UZA II 1090 Wien Österreich
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34
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Hang T, Zhang X, Wu M, Wang C, Ling S, Xu L, Gong Q, Tian C, Zhang X, Zang J. Structural insights into a novel functional dimer of Staphylococcus aureus RNase HII. Biochem Biophys Res Commun 2018; 503:1207-1213. [DOI: 10.1016/j.bbrc.2018.07.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 07/06/2018] [Indexed: 10/28/2022]
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35
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Wang IX, Grunseich C, Fox J, Burdick J, Zhu Z, Ravazian N, Hafner M, Cheung VG. Human proteins that interact with RNA/DNA hybrids. Genome Res 2018; 28:1405-1414. [PMID: 30108179 PMCID: PMC6120628 DOI: 10.1101/gr.237362.118] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 07/27/2018] [Indexed: 12/16/2022]
Abstract
RNA/DNA hybrids form when RNA hybridizes with its template DNA generating a three-stranded structure known as the R-loop. Knowledge of how they form and resolve, as well as their functional roles, is limited. Here, by pull-down assays followed by mass spectrometry, we identified 803 proteins that bind to RNA/DNA hybrids. Because these proteins were identified using in vitro assays, we confirmed that they bind to R-loops in vivo. They include proteins that are involved in a variety of functions, including most steps of RNA processing. The proteins are enriched for K homology (KH) and helicase domains. Among them, more than 300 proteins preferred binding to hybrids than double-stranded DNA. These proteins serve as starting points for mechanistic studies to elucidate what RNA/DNA hybrids regulate and how they are regulated.
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Affiliation(s)
- Isabel X Wang
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA.,Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Christopher Grunseich
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, Maryland 20892, USA
| | - Jennifer Fox
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA.,Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Joshua Burdick
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA.,Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Zhengwei Zhu
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA.,Department of Pediatrics, University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Niema Ravazian
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA
| | - Markus Hafner
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, Maryland 20892, USA
| | - Vivian G Cheung
- Howard Hughes Medical Institute, Chevy Chase, Maryland 20815, USA.,Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA.,Department of Pediatrics, University of Michigan, Ann Arbor, Michigan 48109, USA
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36
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Kojima K, Baba M, Tsukiashi M, Nishimura T, Yasukawa K. RNA/DNA structures recognized by RNase H2. Brief Funct Genomics 2018; 18:169-173. [DOI: 10.1093/bfgp/ely024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Ribonuclease H (RNase H) [EC 3.1.26.4] is an enzyme that specifically degrades RNA from RNA/DNA hybrids. Since its discovery in 1969, the enzyme has been extensively studied for its catalytic mechanism and physiological role. RNase H has been classified into two major families, Type 1 and Type 2. Type 1 enzymes are designated RNase HI in prokaryotes and RNase H1 in eukaryotes, while Type 2 enzymes are designated RNase HII in prokaryotes and RNase H2 in eukaryotes. Type 2 enzymes are able to cleave the 5′-phosphodiester bond of one ribonucleotide embedded in a DNA double strand. Recent studies have shown that RNase H2 is involved in excision of a single ribonucleotide embedded in genomic DNA and removal of an R-loop formed in cells. It is also involved in double-strand break of DNA and its repair. In this review, we aim to outline the structures recognized by RNase H2.
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Affiliation(s)
- Kenji Kojima
- Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Misato Baba
- Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
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37
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Randall JR, Hirst WG, Simmons LA. Substrate Specificity for Bacterial RNases HII and HIII Is Influenced by Metal Availability. J Bacteriol 2018; 200:e00401-17. [PMID: 29084857 PMCID: PMC5786700 DOI: 10.1128/jb.00401-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/23/2017] [Indexed: 12/27/2022] Open
Abstract
We tested the activities of four predicated RNase H enzymes, including two RNase HI-type enzymes, in addition to RNase HII (RnhB) and RNase HIII (RnhC), on several RNA-DNA hybrid substrates with different divalent metal cations. We found that the two RNase HI-type enzymes, YpdQ and YpeP, failed to show activity on the three substrates tested. RNase HII and RNase HIII cleaved all the substrates tested, although the activity was dependent on the metal made available. We show that Bacillus subtilis RNase HII and RNase HIII are both able to incise 5' to a single ribonucleoside monophosphate (rNMP). We show that RNase HIII incision at a single rNMP occurs most efficiently with Mn2+, an activity we found to be conserved among other Gram-positive RNase HIII enzymes. Characterization of RNases HII and HIII with metal concentrations in the physiological range showed that RNase HII can cleave at single rNMPs embedded in DNA while RNase HIII is far less effective. Further, using metal concentrations within the physiological range, RNase HIII efficiently cleaved longer RNA-DNA hybrids lacking an RNA-DNA junction, while RNase HII was much less effective. Phenotypic analysis showed that cells with an rnhC deletion were sensitive to hydroxyurea (HU). In contrast, cells with an rnhB deletion showed wild-type growth in the presence of HU, supporting the hypothesis that RNases HII and HIII have distinct substrate specificities in vivo This work demonstrates how metal availability influences the substrate recognition and activity of RNases HII and HIII, providing insight into their functions in vivoIMPORTANCE RNase H represents a class of proteins that cleave RNA-DNA hybrids, helping resolve R-loops and Okazaki fragments, as well as initiating the process of ribonucleotide excision repair (RER). We investigated the activities of four Bacillus subtilis RNase H enzymes and found that only RNases HII and HIII have activity and that their substrate preference is dependent on metal availability. To understand the factors that contribute to RNase HII and RNase HIII substrate preference, we show that in the presence of metal concentrations within the physiological range, RNases HII and HIII have distinct activities on different RNA-DNA hybrids. This work provides insight into how RNases HII and HIII repair the broad range of RNA-DNA hybrids that form in Gram-positive bacteria.
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Affiliation(s)
- Justin R Randall
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - William G Hirst
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Lyle A Simmons
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
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38
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Malfatti MC, Balachander S, Antoniali G, Koh KD, Saint-Pierre C, Gasparutto D, Chon H, Crouch RJ, Storici F, Tell G. Abasic and oxidized ribonucleotides embedded in DNA are processed by human APE1 and not by RNase H2. Nucleic Acids Res 2017; 45:11193-11212. [PMID: 28977421 PMCID: PMC5737539 DOI: 10.1093/nar/gkx723] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 08/11/2017] [Indexed: 12/13/2022] Open
Abstract
Ribonucleoside 5′-monophosphates (rNMPs) are the most common non-standard nucleotides found in DNA of eukaryotic cells, with over 100 million rNMPs transiently incorporated in the mammalian genome per cell cycle. Human ribonuclease (RNase) H2 is the principal enzyme able to cleave rNMPs in DNA. Whether RNase H2 may process abasic or oxidized rNMPs incorporated in DNA is unknown. The base excision repair (BER) pathway is mainly responsible for repairing oxidized and abasic sites into DNA. Here we show that human RNase H2 is unable to process an abasic rNMP (rAP site) or a ribose 8oxoG (r8oxoG) site embedded in DNA. On the contrary, we found that recombinant purified human apurinic/apyrimidinic endonuclease-1 (APE1) and APE1 from human cell extracts efficiently process an rAP site in DNA and have weak endoribonuclease and 3′-exonuclease activities on r8oxoG substrate. Using biochemical assays, our results provide evidence of a human enzyme able to recognize and process abasic and oxidized ribonucleotides embedded in DNA.
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Affiliation(s)
- Matilde Clarissa Malfatti
- Laboratory of Molecular Biology and DNA repair, Department of Medicine, University of Udine, Udine, Italy
| | - Sathya Balachander
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Giulia Antoniali
- Laboratory of Molecular Biology and DNA repair, Department of Medicine, University of Udine, Udine, Italy
| | - Kyung Duk Koh
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA.,University of California, San Francisco, UCSF, School of Medicine, San Francisco, CA, USA
| | - Christine Saint-Pierre
- Chimie Reconnaissance & Etude Assemblages Biologiques, Université Grenoble Alpes, SPrAM UMR5819 CEA CNRS UGA, INAC/CEA, Grenoble, France
| | - Didier Gasparutto
- Chimie Reconnaissance & Etude Assemblages Biologiques, Université Grenoble Alpes, SPrAM UMR5819 CEA CNRS UGA, INAC/CEA, Grenoble, France
| | - Hyongi Chon
- Developmental Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Robert J Crouch
- Developmental Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Francesca Storici
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Gianluca Tell
- Laboratory of Molecular Biology and DNA repair, Department of Medicine, University of Udine, Udine, Italy
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39
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Baba M, Kojima K, Nakase R, Imai S, Yamasaki T, Takita T, Crouch RJ, Yasukawa K. Effects of neutral salts and pH on the activity and stability of human RNase H2. J Biochem 2017; 162:211-219. [PMID: 28402412 DOI: 10.1093/jb/mvx021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 02/13/2017] [Indexed: 11/14/2022] Open
Abstract
Ribonuclease H (RNase H) specifically degrades the RNA of RNA/DNA hybrid. Recent study has shown that a single ribonucleotide is embedded in DNA double strand at every few thousand base pairs in human genome, and human RNase H2 is involved in its removal. Here, we examined the effects of neutral salts and pH on the activity and stability of human RNase H2. NaCl, KCl, RbCl and NaBr increased the activity to 170-390% at 10-60 mM, while LiCl, LiBr and CsCl inhibited it, suggesting that species of cation, but not anion, is responsible for the effect on activity. NaCl and KCl increased the stability by decreasing the first-order rate constant of the inactivation to 50-60% at 60-80 mM. The activity at 25-35 °C exhibited a narrow bell-shaped pH-dependence with the acidic and alkaline pKe (pKe1 and pKe2) values of 7.3 - 7.6 and 8.1 - 8.8, respectively. Enthalpy changes (ΔH°) of deprotonation were 5 ± 21 kJ mol-1 for pKe1 and 68 ± 25 kJ mol-1 for pKe2. These results suggest that the ionizable groups responsible for pKe1 may be two out of Asp34, Glu35 and Asp141 of DEDD motif, and that for pKe2 may be Lys69 of DSK motif.
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Affiliation(s)
- Misato Baba
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Oiwakecho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kenji Kojima
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Oiwakecho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Rihoko Nakase
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Oiwakecho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Shota Imai
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Oiwakecho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Tomomi Yamasaki
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Oiwakecho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Teisuke Takita
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Oiwakecho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
| | - Robert J Crouch
- Section on Formation of RNA, Division of Developmental Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kiyoshi Yasukawa
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Oiwakecho, Kitashirakawa, Sakyo-ku, Kyoto 606-8502, Japan
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40
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Mentegari E, Crespan E, Bavagnoli L, Kissova M, Bertoletti F, Sabbioneda S, Imhof R, Sturla SJ, Nilforoushan A, Hübscher U, van Loon B, Maga G. Ribonucleotide incorporation by human DNA polymerase η impacts translesion synthesis and RNase H2 activity. Nucleic Acids Res 2017; 45:2600-2614. [PMID: 27994034 PMCID: PMC5389505 DOI: 10.1093/nar/gkw1275] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 12/07/2016] [Indexed: 12/25/2022] Open
Abstract
Ribonucleotides (rNs) incorporated in the genome by DNA polymerases (Pols) are removed by RNase H2. Cytidine and guanosine preferentially accumulate over the other rNs. Here we show that human Pol η can incorporate cytidine monophosphate (rCMP) opposite guanine, 8-oxo-7,8-dihydroguanine, 8-methyl-2΄-deoxyguanosine and a cisplatin intrastrand guanine crosslink (cis-PtGG), while it cannot bypass a 3-methylcytidine or an abasic site with rNs as substrates. Pol η is also capable of synthesizing polyribonucleotide chains, and its activity is enhanced by its auxiliary factor DNA Pol δ interacting protein 2 (PolDIP2). Human RNase H2 removes cytidine and guanosine less efficiently than the other rNs and incorporation of rCMP opposite DNA lesions further reduces the efficiency of RNase H2. Experiments with XP-V cell extracts indicate Pol η as the major basis of rCMP incorporation opposite cis-PtGG. These results suggest that translesion synthesis by Pol η can contribute to the accumulation of rCMP in the genome, particularly opposite modified guanines.
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Affiliation(s)
- Elisa Mentegari
- DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy
| | - Emmanuele Crespan
- DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy
| | - Laura Bavagnoli
- DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy
| | - Miroslava Kissova
- DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy
| | - Federica Bertoletti
- DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy
| | - Simone Sabbioneda
- DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy
| | - Ralph Imhof
- Department of Molecular Mechanisms of Disease, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Shana J Sturla
- Department of Health Sciences and Technology, ETH Zurich, Schmelzbergstrasse 9, CH-8092 Zürich, Switzerland
| | - Arman Nilforoushan
- Department of Health Sciences and Technology, ETH Zurich, Schmelzbergstrasse 9, CH-8092 Zürich, Switzerland
| | - Ulrich Hübscher
- Department of Molecular Mechanisms of Disease, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Barbara van Loon
- Department of Molecular Mechanisms of Disease, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Giovanni Maga
- DNA Enzymology & Molecular Virology and Cell Nucleus & DNA replication Units, Institute of Molecular Genetics IGM-CNR, via Abbiategrasso 207, I-27100 Pavia, Italy
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41
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Harris RC, Boschitsch AH, Fenley MO. Numerical Difficulties Computing Electrostatic Potentials Near Interfaces with the Poisson–Boltzmann Equation. J Chem Theory Comput 2017. [DOI: 10.1021/acs.jctc.7b00487] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Robert C. Harris
- Department
of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, Maryland 21201, United States
| | | | - Marcia O. Fenley
- Institute
of Molecular Biophysics, Florida State University, Tallahassee, Florida 32306, United States
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42
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Abstract
Genomic DNA is transiently contaminated with ribonucleotide residues during the process of DNA replication through misincorporation by the replicative DNA polymerases α, δ and ε, and by the normal replication process on the lagging strand, which uses RNA primers. These ribonucleotides are efficiently removed during replication by RNase H enzymes and the lagging strand synthesis machinery. However, when ribonucleotides remain in DNA they can distort the DNA helix, affect machineries for DNA replication, transcription and repair, and can stimulate genomic instabilities which are manifest as increased mutation, recombination and chromosome alterations. The genomic instabilities associated with embedded ribonucleotides are considered here, along with a discussion of the origin of the lesions that stimulate particular classes of instabilities.
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Affiliation(s)
- Hannah L Klein
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA.
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43
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Heider MR, Burkhart BW, Santangelo TJ, Gardner AF. Defining the RNaseH2 enzyme-initiated ribonucleotide excision repair pathway in Archaea. J Biol Chem 2017; 292:8835-8845. [PMID: 28373277 PMCID: PMC5448109 DOI: 10.1074/jbc.m117.783472] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 03/31/2017] [Indexed: 11/06/2022] Open
Abstract
Incorporation of ribonucleotides during DNA replication has severe consequences for genome stability. Although eukaryotes possess a number of redundancies for initiating and completing repair of misincorporated ribonucleotides, archaea such as Thermococcus rely only upon RNaseH2 to initiate the pathway. Because Thermococcus DNA polymerases incorporate as many as 1,000 ribonucleotides per genome, RNaseH2 must be efficient at recognizing and nicking at embedded ribonucleotides to ensure genome integrity. Here, we show that ribonucleotides are incorporated by the hyperthermophilic archaeon Thermococcus kodakarensis both in vitro and in vivo and a robust ribonucleotide excision repair pathway is critical to keeping incorporation levels low in wild-type cells. Using pre-steady-state and steady-state kinetics experiments, we also show that archaeal RNaseH2 rapidly cleaves at embedded ribonucleotides (200-450 s-1), but exhibits an ∼1,000-fold slower turnover rate (0.06-0.17 s-1), suggesting a potential role for RNaseH2 in protecting or marking nicked sites for further processing. We found that following RNaseH2 cleavage, the combined activities of polymerase B (PolB), flap endonuclease (Fen1), and DNA ligase are required to complete ribonucleotide processing. PolB formed a ribonucleotide-containing flap by strand displacement synthesis that was cleaved by Fen1, and DNA ligase sealed the nick for complete repair. Our study reveals conservation of the overall mechanism of ribonucleotide excision repair across domains of life. The lack of redundancies in ribonucleotide repair in archaea perhaps suggests a more ancestral form of ribonucleotide excision repair compared with the eukaryotic pathway.
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Affiliation(s)
| | - Brett W Burkhart
- the Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80521
| | - Thomas J Santangelo
- the Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado 80521
| | - Andrew F Gardner
- From New England Biolabs, Inc., Ipswich, Massachusetts 01938 and
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44
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Gupta R, Chatterjee D, Glickman MS, Shuman S. Division of labor among Mycobacterium smegmatis RNase H enzymes: RNase H1 activity of RnhA or RnhC is essential for growth whereas RnhB and RnhA guard against killing by hydrogen peroxide in stationary phase. Nucleic Acids Res 2016; 45:1-14. [PMID: 27899559 PMCID: PMC5224475 DOI: 10.1093/nar/gkw1046] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 10/16/2016] [Accepted: 10/20/2016] [Indexed: 02/05/2023] Open
Abstract
RNase H enzymes sense the presence of ribonucleotides in the genome and initiate their removal by incising the ribonucleotide-containing strand of an RNA:DNA hybrid. Mycobacterium smegmatis encodes four RNase H enzymes: RnhA, RnhB, RnhC and RnhD. Here, we interrogate the biochemical activity and nucleic acid substrate specificity of RnhA. We report that RnhA (like RnhC characterized previously) is an RNase H1-type magnesium-dependent endonuclease with stringent specificity for RNA:DNA hybrid duplexes. Whereas RnhA does not incise an embedded mono-ribonucleotide, it can efficiently cleave within tracts of four or more ribonucleotides in duplex DNA. We gained genetic insights to the division of labor among mycobacterial RNases H by deleting the rnhA, rnhB, rnhC and rnhD genes, individually and in various combinations. The salient conclusions are that: (i) RNase H1 activity is essential for mycobacterial growth and can be provided by either RnhC or RnhA; (ii) the RNase H2 enzymes RnhB and RnhD are dispensable for growth and (iii) RnhB and RnhA collaborate to protect M. smegmatis against oxidative damage in stationary phase. Our findings highlight RnhC, the sole RNase H1 in pathogenic mycobacteria, as a candidate drug discovery target for tuberculosis and leprosy.
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Affiliation(s)
- Richa Gupta
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Debashree Chatterjee
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Michael S Glickman
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA .,Division of Infectious Diseases, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Stewart Shuman
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
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45
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Evich M, Spring-Connell AM, Storici F, Germann MW. Structural Impact of Single Ribonucleotide Residues in DNA. Chembiochem 2016; 17:1968-1977. [PMID: 27504600 DOI: 10.1002/cbic.201600385] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Indexed: 11/09/2022]
Abstract
Single ribonucleotide intrusions represent the most common nonstandard nucleotide type found incorporated in genomic DNA, yet little is known of their structural impact. This lesion incurs genomic instability in addition to affecting the physical properties of the DNA. To probe for structural and dynamic effects of single ribonucleotides in various sequence contexts-AxC, CxG, and GxC, where x=rG or dG-we report the structures of three single-ribonucleotide-containing DNA duplexes and the corresponding DNA controls. The lesion subtly and locally perturbs the structure asymmetrically on the 3' side of the lesion in both the riboguanosine-containing and the complementary strand of the duplex. The perturbations are mainly restricted to the sugar and phosphodiester backbone. The ribose and 3'-downstream deoxyribose units are predominately in N-type conformation; backbone torsion angles ϵ and/or ζ of the ribonucleotide or upstream deoxyribonucleotide are affected. Depending on the flanking sequences, the C2'-OH group forms hydrogen bonds with the backbone, 3'-neighboring base, and/or sugar. Interestingly, even in similar purine-rG-pyrimidine environments (A-rG-C and G-rG-C), a riboguanosine unit affects DNA in a distinct manner and manifests different hydrogen bonds, which makes generalizations difficult.
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Affiliation(s)
- Marina Evich
- Department of Chemistry, Georgia State University, Atlanta, GA, 30303, USA
| | | | - Francesca Storici
- Department of Biology, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Markus W Germann
- Department of Chemistry, Georgia State University, Atlanta, GA, 30303, USA.
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46
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Nisa-Martínez R, Molina-Sánchez MD, Toro N. Host Factors Influencing the Retrohoming Pathway of Group II Intron RmInt1, Which Has an Intron-Encoded Protein Naturally Devoid of Endonuclease Activity. PLoS One 2016; 11:e0162275. [PMID: 27588750 PMCID: PMC5010178 DOI: 10.1371/journal.pone.0162275] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 08/21/2016] [Indexed: 11/21/2022] Open
Abstract
Bacterial group II introns are self-splicing catalytic RNAs and mobile retroelements that have an open reading frame encoding an intron-encoded protein (IEP) with reverse transcriptase (RT) and RNA splicing or maturase activity. Some IEPs carry a DNA endonuclease (En) domain, which is required to cleave the bottom strand downstream from the intron-insertion site for target DNA-primed reverse transcription (TPRT) of the inserted intron RNA. Host factors complete the insertion of the intron. By contrast, the major retrohoming pathway of introns with IEPs naturally lacking endonuclease activity, like the Sinorhizobium meliloti intron RmInt1, is thought to involve insertion of the intron RNA into the template for lagging strand DNA synthesis ahead of the replication fork, with possible use of the nascent strand to prime reverse transcription of the intron RNA. The host factors influencing the retrohoming pathway of such introns have not yet been described. Here, we identify key candidates likely to be involved in early and late steps of RmInt1 retrohoming. Some of these host factors are common to En+ group II intron retrohoming, but some have different functions. Our results also suggest that the retrohoming process of RmInt1 may be less dependent on the intracellular free Mg2+ concentration than those of other group II introns.
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Affiliation(s)
- Rafael Nisa-Martínez
- Structure, Dynamics and Function of Rhizobacterial Genomes, Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Calle Profesor Albareda 1, 18008, Granada, Spain
| | - María Dolores Molina-Sánchez
- Structure, Dynamics and Function of Rhizobacterial Genomes, Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Calle Profesor Albareda 1, 18008, Granada, Spain
| | - Nicolás Toro
- Structure, Dynamics and Function of Rhizobacterial Genomes, Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, Calle Profesor Albareda 1, 18008, Granada, Spain
- * E-mail:
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47
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Williams JS, Lujan SA, Kunkel TA. Processing ribonucleotides incorporated during eukaryotic DNA replication. Nat Rev Mol Cell Biol 2016; 17:350-63. [PMID: 27093943 PMCID: PMC5445644 DOI: 10.1038/nrm.2016.37] [Citation(s) in RCA: 133] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The information encoded in DNA is influenced by the presence of non-canonical nucleotides, the most frequent of which are ribonucleotides. In this Review, we discuss recent discoveries about ribonucleotide incorporation into DNA during replication by the three major eukaryotic replicases, DNA polymerases α, δ and ε. The presence of ribonucleotides in DNA causes short deletion mutations and may result in the generation of single- and double-strand DNA breaks, leading to genome instability. We describe how these ribonucleotides are removed from DNA through ribonucleotide excision repair and by topoisomerase I. We discuss the biological consequences and the physiological roles of ribonucleotides in DNA, and consider how deficiencies in their removal from DNA may be important in the aetiology of disease.
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Affiliation(s)
- Jessica S. Williams
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC 27709, United States
| | - Scott A. Lujan
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC 27709, United States
| | - Thomas A. Kunkel
- Genome Integrity and Structural Biology Laboratory, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC 27709, United States
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48
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Davis RR, Shaban NM, Perrino FW, Hollis T. Crystal structure of RNA-DNA duplex provides insight into conformational changes induced by RNase H binding. Cell Cycle 2015; 14:668-73. [PMID: 25664393 DOI: 10.4161/15384101.2014.994996] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
RNA-DNA hybrids play essential roles in a variety of biological processes, including DNA replication, transcription, and viral integration. Ribonucleotides incorporated within DNA are hydrolyzed by RNase H enzymes in a removal process that is necessary for maintaining genomic stability. In order to understand the structural determinants involved in recognition of a hybrid substrate by RNase H we have determined the crystal structure of a dodecameric non-polypurine/polypyrimidine tract RNA-DNA duplex. A comparison to the same sequence bound to RNase H, reveals structural changes to the duplex that include widening of the major groove to 12.5 Å from 4.2 Å and decreasing the degree of bending along the axis which may play a crucial role in the ribonucleotide recognition and cleavage mechanism within RNase H. This structure allows a direct comparison to be made about the conformational changes induced in RNA-DNA hybrids upon binding to RNase H and may provide insight into how dysfunction in the endonuclease causes disease.
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Affiliation(s)
- Ryan R Davis
- a Department of Biochemistry; Center for Structural Biology ; Wake Forest School of Medicine ; Winston-Salem , NC USA
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49
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SURESH GORLE, PRIYAKUMAR UDEVA. Atomistic details of the molecular recognition of DNA-RNA hybrid duplex by ribonuclease H enzyme. J CHEM SCI 2015. [DOI: 10.1007/s12039-015-0942-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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50
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Feng S, Cao Z. Is the role of human RNase H2 restricted to its enzyme activity? PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2015; 121:66-73. [PMID: 26603688 DOI: 10.1016/j.pbiomolbio.2015.11.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Revised: 11/12/2015] [Accepted: 11/17/2015] [Indexed: 11/16/2022]
Abstract
In human cells, ribonuclease (RNase) H2 complex is the predominant source of RNase H activities with possible roles in nucleic acid metabolism to preserve genome stability and to prevent immune activation. Dysfunction mutations in any of the three subunits of human RNase H2 complex can result in embryonic/perinatal lethality or cause Aicardi-Goutières syndrome (AGS). Most recently, increasing findings have shown that human RNase H2 proteins play roles beyond the RNase H2 enzymatic activities in health and disease. Firstly, the biochemical and structural properties of human RNase H2 proteins allow their interactions with various partner proteins that may support functions other than RNase H2 enzymatic activities. Secondly, the disparities of clinical presentations of AGS with different AGS-mutations and the biochemical and structural analysis of AGS-mutations, especially the results from both AGS-knockin and RNase H2-null mouse models, suggest that human RNase H2 complex has certain cellular functions beyond the RNase H2 enzymatic activities to prevent the innate-immune-mediated inflammation. Thirdly, the subunit proteins RNASEH2A and RNASEH2B respectively, not related to the RNase H2 enzymatic activities, have been shown to play a certain role in the pathophysiological processes of different cancer types. In this minireview, we aims to provide a brief overview of the most recent investigations into the biological functions of human RNase H2 proteins and the underlying mechanisms of their actions, emphasizing on the new insights into the roles of human RNase H2 proteins playing beyond the RNase H2 enzymatic activities in health and disease.
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Affiliation(s)
- Shaolong Feng
- The School of Public Health, University of South China, Hengyang 421001, China.
| | - Zhaohui Cao
- The School of Pharmacy and Life Sciences, University of South China, Hengyang 421001, China
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